Present address: Department of Biology, Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan.
Localized lesions of arcopallium intermedium of the lateral forebrain caused a handling-cost aversion in the domestic chick performing a binary choice task
Article first published online: 24 OCT 2006
European Journal of Neuroscience
Volume 24, Issue 8, pages 2314–2326, October 2006
How to Cite
Aoki, N., Csillag, A. and Matsushima, T. (2006), Localized lesions of arcopallium intermedium of the lateral forebrain caused a handling-cost aversion in the domestic chick performing a binary choice task. European Journal of Neuroscience, 24: 2314–2326. doi: 10.1111/j.1460-9568.2006.05090.x
- Issue published online: 24 OCT 2006
- Article first published online: 24 OCT 2006
- Received 6 October 2005, revised 9 July 2006, accepted 3 August 2006
- consummatory behavior;
- foraging behavior;
- frontal cortex;
- impulsive choice;
- nucleus accumbens
Behavioral effects of handling cost (time and/or energetic cost for food consumption) on choice were examined using domestic chicks trained in operant task reinforced by delayed food rewards. When scattered sesame was delivered in more demanding conditions, a colored cue bead associated with six grains (‘large’ and ‘costly’ reward) was chosen progressively less frequently against another bead associated with one grain (‘small’ and ‘not costly’ reward). The choice thus proved to be highly sensitive to the anticipated handling cost. Excitotoxic lesion of the bilateral arcopallium intermedium also selectively reduced the choice of the six grains, while leaving actual cost investment (number of pecks and handling time) unaltered. No significant changes occurred in choices between one grain of sesame (‘small’ and ‘not costly’ reward) and one grain of barley (or a ball composed of six sesame grains glued by starch; ‘large’ and ‘not costly’ reward), indicating that choice based on anticipated food amount was not impaired. On the other hand, lesion of the ventral striatum did not change the choice ratio in any trial types. Operant peck latencies somewhat depended on food rewards, but were not affected by lesions of the arcopallium or the ventral striatum. The arcopallium could contribute to foraging behaviors by enabling chicks to overcome the handling cost, thus gaining more beneficial food. Furthermore, the present results indicate doubly dissociated functional roles of the ventral striatum and the arcopallium, the former in the cost of traveling for food and the latter in the cost of handling food, respectively.